1. Field of the Invention
The present invention relates to a displacement detection type six-axis force sensor.
2. Description of the Related Art
A displacement detection type force sensor is configured to detect, when a force (or load) is applied to a sensor body, a displacement of the sensor body accompanying the deformation of the sensor body caused by the applied force and thereby detect the force based on the detected displacement. For example, Japanese Patent No. 4271475 (JP4271475B2) discloses a force sensor that detects a displacement by detecting a change in capacitance provided at a predetermined position on a sensor body. The force sensor includes an outer box-like structure and an inner box-like structure, wherein the side and top surfaces of the outer box-like structure and the side and top surface of the inner box-like structure are arranged so as to oppose each other to form a gap continuously extending throughout the sensor body. A plurality of pairs of electrodes are respectively arranged at predetermined locations in the gap in such a manner that the electrodes of each pair are opposed to each other in a direction of any one axis of a three-axis rectangular coordinate system, so as to form capacitance between the opposing electrodes of each pair (i.e., to form a capacitor). When the outer box-like structure is deformed by a force (or load), the shape and dimensions of the gap change correspondingly, and the capacitance between the respective opposing electrodes changes. From this change in capacitance, a displacement of the outer box-like structure relative to the inner box-like structure is calculated, and, based on the calculated displacement, a force component in each axis direction and a moment component about each axis, of the force applied to the outer box-like structure, can be detected.